Asian Pacific Journal of Tropical Medicine

421-425

Authors: Fengying Huang, Qiuping Meng, Guanghong Tan, Yonghao Huang, Hua Wang, Wenli Mei, Haofu Dai

Objective To analysis and identify a bacterium strain isolated from laboratory breeding mouse far away from a hospital. Methods Phenotype of the isolate was investigated by conventional microbiological methods, including Gram–staining, colony morphology, tests for haemolysis, catalase, coagulase, and antimicrobial susceptibility test. The mecA and 16S rRNA genes were amplified by the polymerase chain reaction (PCR) and sequenced. The base sequence of the PCR product was compared with known 16S rRNA gene sequences in the GenBank database by phylogenetic analysis and multiple sequence alignment. Results The isolate in this study was a gram positive, coagulase negative, and catalase positive coccus. The isolate was resistant to oxacillin, methicillin, penicillin, ampicillin, cefazolin, ciprofloxacin erythromycin, et al. PCR results indicated that the isolate was mecA gene positive and its 16S rRNA was 1 465 bp. Phylogenetic analysis of the resultant 16S rRNA indicated the isolate belonged to genus Saphylococcus, and multiple sequence alignment showed that the isolate was Saphylococcus haemolyticus with only one base difference from the corresponding 16S rRNA deposited in the GenBank. Conclusions 16S rRNA gene sequencing is a suitable technique for non–specialist researchers. Laboratory animals are possible sources of lethal pathogens, and researchers must adapt protective measures when they manipulate animals.

430-435

Authors: Sarita Kumar, Anita Thomas, MKK Pillai

Objective To evaluate the effects of deltamethrin against field-collected adults of Aedes aegypti L. (Ae. aegypti). Methods The adults were selected with 0.025% deltamethrin for 40 successive generations. The selected adults were tested with 4% DDT and the emerging larvae were tested with various insecticides to study the cross-resistance spectrum. The knockdown and irritability studies were carried out in adult mosquitoes to investigate their behavioural response to deltamethrin. Results Forty generations of selection with deltamethrin resulted in only 3.8—fold resistance in the adults of Ae. aegypti. The adults of parent (PS) and selected strains (DAS) exhibited only 0.8-fold cross resistance to 4% DDT. The larvae emerging from the PS and DAS strains did not develop appreciable levels of resistance to various insecticides tested. The knockdown studies revealed KT50 of 14.4 min in PS adults with no signs of recovery even after 24 h. The DAS strains could develop only 1.2 to 1.3-fold knockdown resistance (KDR). The knockdown response of DDT was though 5–6 times slower than deltamethrin but the continued response in deltamethrin-selected adults caused only 1.2-fold KDR. The PS and DAS strains exhibited significant irritability response towards deltamethrin and DDT. The DAS strains showed 5–6 fold increased irritability to deltamethrin as compared to the PS strain. Conclusions The above results suggest the prolonged effective use of deltamethrin against Ae. aegypti as an adulticide.

442-446

Authors: Jude E Okokon, Paul A Nwafor, Ukeme E Andrew

Objective To evaluate antiplasmodial and analgesic activities of ethanolic leaf extract/fractions of Panicum maximum. Methods The crude leaf extract (47–190 mg/kg) and fractions (chloroform, ethyl acqeous and methanol; 96 mg/kg) of Panicum maximum were investigated for antiplasmodial activity against chloroquine sensitive Plasmodium berghei infections in mice and for analgesic activity against chemical and heat-induced pains. The antiplasmodial activity during early and established infections as well as prophylactic were investigated. Artesunate at 5 mg/kg and pyrimethamine at 1.2 mg/kg were used as positive controls. Analgesic activity of the crude extract/fractions was also evaluated against acetic acid, formalin and heat-induced pains. Results The extract and its fractions dose-dependently reduced parasitaemia induced by chloroquine sensitive Plasmodium berghei infection in prophylactic, suppressive and curative models in mice. These reductions were statistically significant (P<0.001). They also improved the mean survival time from 13 to 28 days compared with control (P<0.001). The activities of extract/fractions were incomparable to that of the standard drugs (Artesunate and pyrimethamine). On chemically and thermally-induced pains, the extract inhibited acetic acid and formalin-induced inflammation as well as hot plate-induced pain in mice. These inhibitions were statistically significant (P<0.001) and in a dose-dependent fashion. Conclusions Panicum maximum leaf extract has antiplasmodial and analgesic activities which may in part be mediated through the chemical constituents of the plant.

451-456

Authors: Gollapalle Lakshminaraya Shastry Viswanatha, Shylaja Hanumanthappa, Nandakumar Krishnadas, Srinath Rangappa

Objective To evaluate antidiarrheal activity of the fractions of aqueous extract from stem barks of Thespesia populnea (Malvaceae). Methods From the aqueous extract three fractions namely ethyl acetate fraction (EAF), methanolic fraction (MF) and residue fraction (RF) were made and studied for antidiarrheal activity. Antidiarrheal activity of the fractions were evaluated in castor oil induced diarrhea, prostaglandin E2 (PG-E2) induced diarrhea and charcoal meal test as in vivo models and the most potent fraction was further evaluated with in vitro models to determine the possible antimotility effect. Results In castor oil induced diarrhea model, the RF (10, 25, 50 and 100 mg/kg, po.) and MF (100 mg/kg, po.) has significantly reduced the cumulative wet faecal mass, where as the EAF have not shown any significant antidiarrheal activity, RF was found to be more potent than MF. Based on these results and percentage yield, only RF was evaluated in PG-E2 induced enteropooling and charcoal meal test. RF (10, 25 and 50 mg/kg) had shown significant inhibition of PG-E2 induced secretions (antisecretory) and decreased the movement of charcoal in charcoal meal test indicating its antimotility activity. Furthermore, RF has showed significant inhibition of acetylcholine, histamine and BaCl2 induced contractions on rat colon, guinea pig ileum and rabbit jejunum with EC50 values of 241.7, 303.1 and 286.1 μg/mL, respectively indicating the antimotility effect of RF. The phytochemical analysis of RF showed presence of gums and mucilages and the possible mechanism may be the combination inhibition of elevated prostaglandin biosynthesis and reduced propulsive movement of the intestine. Conclusions RF possesses good antidiarrheal activity comparing with other two fractions and the possible mechanism thought to be associated with combination of antisecretory and antimolity.

462-465

Authors: Murugesan Gnanadesigan, Sundaram Ravikumar, Samuel Jacob Inbaneson

Objective To identify the hepatoprotective and antioxidant activity of Luminetzera racemosa (L. racemosa) bark extract. Methods Wistar albino rats were divided into 6 groups: Group 1 served as control; Group 2 served as hepatotoxin (CCL4 treated) group; Group 3 served as positive control (Silymarin) treated groups; Group 4, 5 and 6 served as (100, 200 and 300 mg/kg bw p.o.) L. racemosa bark extract treated groups. Moreover, in vitro antioxidant indexes, including DPPH, hydroxyl radical scavenging activity (HRSA), NO, ferric reducing antioxidant power (FRAP), lipid hydroperoxide (LPO) and super oxide dismutase (SOD) were also analyzed in the bark extract. Results The results suggested that, the level of serum glutamate oxyloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), alkaline phosphatise (ALP), bilurubin, cholesterol, sugar and lactate dehydrogenase (LDH) were significantly (P<0.05) increased in hepatotoxin treated rats when compared with the control group. But, the maximum reduction of SGOT [(225.36±13.65) IU/L], SGPT [(96.85±17.36) IU/L], ALP [(315.37±17.16) IU/L], bilirubin [(2.97±0.46) mg/dL], cholesterol [(163.73±17.54) mg/dL], sugar [(127.35±27.35) mg/dL] and LDH [(1 784.00±268.36) IU/L] were observed with 300 mg/kg bw of bark extract treated rats. Histopathological scores showed that, no visible changes were observed with high dose (300 mg/kg bw) of bark extract treated rats except mild fatty changes. The in vitro antioxidant assays showed that, the IC50 values were observed as (44.17±6.87) μg/mL, (42.45±2.81)μg/mL, (62.37±3.98)μg/mL, (54.24±3.09)μg/mL, (87.25±5.90) μg/mL and (71.54±5.42)μg/mL for DPPH, HRSA, NO, FRAP, LPO and SOD radical scavenging activities, respectively. Conclusions The hepatoprotective and antioxidant activities of the bark extract might be to the presence of unique chemical classes such as flavonoids, alkaloids and polyphenols.

470-474

Authors: Nilesh Kumar Jain, Abhay K Singhai

Objective To investigate and compare the hepatoprotective effects of crude ethanolic and aqueous extracts of Phyllanthus acidus (L.) Skeels (P. acidus) leaves on acetaminophen (APAP) and thioacetamide (TAA) induced liver toxicity in wistar rats. Silymarin was the reference hepatoprotective agent. Methods In two different sets of experiments, the P. acidus extracts (200 and 400 mg/kg, body weight) and silymarin (100 mg/kg, body weight) were given orally for 7 days and a single dose of APAP (2 g/kg, per oral) or TAA (100 mg/kg, subcutaneous) were given to rats. The level of serum aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), total bilirubin and total protein were monitored to assess hepatotoxicity and hepatoprotection. Results APAP or TAA administration caused severe hepatic damage in rats as evident from significant rise in serum AST, ALT, ALP, total bilirubin and concurrent depletion in total serum protein. The P. acidus extracts and silymarin prevented the toxic effects of APAP or TAA on the above serum parameters indicating the hepatoprotective action. The aqueous extract was found to be more potent than the corresponding ethanolic extract against both toxicants. The phenolic and flavonoid content (175.02±4.35 and 74.68±1.28, respectively) and 2,2-diphenyl-1-picrylhydrazil (DPPH) [IC50 = (33.2±0.31)μg/mL] scavenging potential was found maximum with aqueous extract as compared to ethanolic extract. Conclusions The results of present study suggests that the aqueous extract of P. acidus leaves has significant hepatoprotective activity on APAP and TAA induced hepatotoxicity, which might be associate with its high phenolic and flavonoid content and antioxidant properties.

478-481

Authors: CH Rasul, MA Bakar, AA Mamun, MS Siraz, RU Zaman

Objective To determine the magnitude and outcome of influenza in southern part of Bangladesh and also to identify intrusion of novel influenza virus. Methods This study was conducted for two years (2008–2009) in outpatient and inpatient department of both paediatrics and medicine discipline of Khulna Medical College Hospital. Nasal and throat swab specimens were collected from each influenza like illness (ILI) case and kept together in a virus transport media and transported to international centre for diarrhoeal disease and research, Bangladesh laboratory. Influenza virus was detected by rRT-PCR including types and subtypes. Results A total of 526 patients were enrolled during the study period with the mean (SD) age of 19 (17) years. Identification of influenza virus was 14% and positive cases were mostly found in under-five children (24%). The vast majority (88%) of influenza cases were found during April to September. Virus detection rate was higher in inpatient department (IPD) (21%) than in outpatient department (12%). The dominant virus type and subtype was influenza A (87%) and H3 (49%), respectively. Type A was significantly higher than type B in causing severe illness compared to ILI (OR=7.04, 95% CI: 2.76–18.7, P<0.01). Headache and chest indrawing was found in significantly higher proportion (P<0.05) in influenza positive IPD cases. Among 31 hospitalized cases majority (77%) recovered completely except two cases that needed referral for additional support. Conclusions Influenza mostly affected under-five children and young adult. The peak season here was late summer and rainy season.

486-491

Authors: C Thenmozhi, R Sankar, V Karuppiah, P Sampathkumar

Objective To isolate marine bacteria, statistically optimize them for maximum asparaginase production. Methods In the present study, statistically based experimental designs were applied to maximize the production of L-asparaginase from bacterial strain of Bacillus cereus (B. cereus) MAB5 (HQ675025) isolated and identified by 16S rDNA sequencing from mangroves rhizosphere sediment. Results Plackett-Barman design was used to identify the interactive effect of the eight variables viz. yeast extract, soyabean meal, glucose, magnesium sulphate, KH2PO4, wood chips, aspargine and sodium chloride. All the variables are denoted as numerical factors and investigated at two widely spaced intervals designated as −1 (low level) and +1 (high level). The effect of individual parameters on L-asparaginase production was calculated. Soyabean meal, aspargine, wood chips and sodium chloride were found to be the significant among eight variables. The maximum amount of L-asparaginase produced (51.54 IU/mL) from the optimized medium containing soyabean meal (6.282 8 g/L), aspargine (5.5 g/L), wood chips (1.383 8 g/L) and NaCl (4.535 4 g/L). Conclusions The study revealed that, it is useful to produce the maximum amount of L-asparaginase from B. cereus MAB5 for the treatment of various infections and diseases.

498-504

Authors: Ahmad Ali Hanafi-Bojd, Shahyad Azari-Hamidian, Vatandoost Hassan, Charrahy Zabihollah

Malaria is a main vector-borne public health problem in Iran. The last studies on Iranian mosquitoes show 31 Anopheles species including different sibling species and genotypes, eight of them are reported to play role in malaria transmission. The objective of this study is to provide a reference for malaria vectors of Iran and to map their spatial and temporal distribution in different climatic zones. Shape files of administrative boundaries and climates of Iran were provided by National Cartographic Center. Data on distribution and seasonal activity of malaria vectors were obtained from different sources and a databank in district level was created in Excel 2003, inserted to the shape files and analyzed by ArcGIS 9.2 to provide the maps. Anopheles culicifacies Giles s.l., Anopheles dthali Patton, Anopheles fluviatilis James s.l., Anopheles maculipennis Meigen s.l., Anopheles sacharovi Favre, Anopheles stephensi Liston, and Anopheles superpictus Grassi have been introduced as primary and secondary malaria vectors and Anopheles pulcherrimus Theobald as a suspected vector in Iran. Temporal distribution of anopheline mosquitoes is restricted to April–December in northern Iran, however mosquitoes can be found during the year in southern region. Spatial distribution of malaria vectors is different based on species, thus six of them (except for Anopheles maculipennis s.l. and Anopheles sacharovi) are reported from endemic malarious area in southern and southeastern areas of Iran. The climate of this part is usually warm and humid, which makes it favorable for mosquito rearing and malaria transmission. Correlation between climate conditions and vector distribution can help to predict the potential range of activity for each species and preparedness for malaria epidemics.